As shown in FIG. 1, the indoor unit 100 of a pipe-ventilated air conditioner in the prior art comprises an indoor unit body 110, and an air outlet component 120 arranged at the air outlet of the indoor unit body. Wherein, the air outlet component 120 comprises an air outlet frame 121, air deflectors 122 for guiding the directions of the air discharged from the air conditioner, and a driving device (not shown) for driving the air deflectors to rotate. In the prior art, the control method for the air deflectors is as follows: when the air conditioner is running, according to the air volume levels, the temperature and so on, which are input by the user, the controller determines the air guide angle of the air deflectors, and sends control signals to the driving device of the air deflectors, and the driving device drives the air deflectors to rotate to a required air guide angle. The problem of this control method is that, when the air conditioner is running, if the user does not adjust the air guide angle of the air deflectors, the air deflectors will remain the default angle all the time and will not be adjusted automatically according to the environment, thereby causing poor comfort.